Australian police described as “depraved” the case of a six-year-old boy obtained by his gay male parents via a surrogate and then sexually abused by them and others. Authorities in Australia and the United States worked together to bring to justice the men who had lived in the north Queensland city of Cairns and presented themselves as loving dads.

But the baby boy they obtained from a Russian surrogate in 2005 and formally adopted had been offered to others for sexual exploitation from a very young age. “None of these cases are very good,” Queensland detective inspector Jon Rouse,who heads the taskforce which investigates online child exploitation and abuse,said

“What’s pretty sad about this one is the way this child came into their lives. It’s just really a tragedy. It’s extremely depraved.” It is not known whether the boy was conceived with one of the men’s sperm but he had been living as the couple’s son when a chance discovery in New Zealand put police on their track. Authorities investigating a child sex offender in Wellington had found images of the boy on the man’s computer.

The images were not illegal but they raised red flags with Australian police who saw them as “modelling shots”. Further investigations unearthed chat logs between the couple and other child sex offenders. When police raided the couples’ home,while they were in the United States,they found enough material on laptops and other devices to ensure their arrest and the boy’s removal from their care.

Both men were arrested in California in early 2012 and charged. Last weekend,one was jailed for 40 years,the other is awaiting sentencing. Rouse said police were determined to ensure that all offenders were tracked down. “We are talking about a fairly extensive network of child sex offenders,” he said.